High
E 01 on Keston C36

Your boiler is failing to light the flame needed to produce heat or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Ignition failure - the boiler has attempted to light five times and not succeeded - check the gas supply is on.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E 02View →E 04View →

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